Reduction of oxids.



. 0.. ARSEM.

REDUCTION OF OXIDS.

APPLICATION FILED JAN. 6, 1909.

Patented Apr.

Witnesses I Inventbr' William Gffr'sem,

WILLIAM c. ARSEM, or SCHENECTADY, NEW YORK, Assmnon TO GENERAL ELEC- TRIO COMPANY, A conronarxon ornnw YORK.

I REDUCTIQN 0F OXIDS.

Specification of Letters Patent.

Patented Apr. 1%, 1912.

Application filed January 6, 1909. Serial No. 470,918.

To all whom it may concern:

Be it known that I, VILLIAM C. ARsEM, a citizen of the United States, residing at Schenectady, county of Sdhenectady, State of New York, have invented certain new and useful Improvements in Reduction of Oxide, of which-the following is a specification;

Mypresent invention comprises a process for the production of an oXid of a metal from a higher oXid of that metal.

The process is applicable generally to metals which form more than one OXld and is of particular value for the preparation of the lower oxids of such metals astungsten, molybdenum, vanadium, uranium and titanium.

As one embodiment of my invention I will hereinafter describe it as applied to the pro .duction of the brown oxid of tungsten, this being of the chemical composition VVO and obtained by reduction of the yellow oxid VVO Carbon monoxid is used by me as the reducing agent and the details. of procedure are hereinafter set forth.

An apparatus in which my process can be conveniently carried out is shown in the accompanying drawing, and comprises an outer clay crucible 1 provided with a cover 2 and inclosing a smaller graphite or clay crucible 3 having. a cover l. The W 0 to be reduced is placed in the inner or graphite or clay crucible and the latter is entirely in closed by a carbon packing 6. The crucibles are then placed in an electric mufiie furnace or in a suitable gas. furnace and heated up to about 800 C. The air initially resent in the carbon packing and in the W powder produces 00 by action on the carbon packing and this GO reduces a part of the WO to'WO thus This CO by diffusion, comes in contact Wit-lithe carbon packing and reaction takes place, thus:

' CO +C:2CO I thereby reforming G0 which again'diffu'ses into the remaining W0, and continues the reduction. The porosity of the inner graphite crucible materially favors rapid diffusion 1 reduces it entirely to W 0 The low tem-- perature of treatment and the entire absence of contact between the carbon and the tungstic acid insure absence of tungsten cairbid or free carbon in the resultant product. The VVO thus prepared is a very suitable material for use in the production of lamp filaments. It may be used either as the basis for the squirting mixture, or as the material from which the metal itself is obtained beforeshaping into threads.

As above indicated, the method is equally applicable to the oxids of molybdenum and other metals, thus affording an easy means of obtaining low oxids, some of which have heretofore been almost unattainable except in an impure state.

hat I claim new anddesire to secure by Letters Patent of the United States, is,-

1. The method of producing a low oxid of a metal which consists in introducing the higher oxid into a pervious receptacle, creating a heated atmosphere of carbon mon- .oxid around the receptacle, and thereby reducing the higher oxid by diffusion of the carbon monoxid into the receptacle.

2. The method of producing a low oXid of a metal, which consists in introducing the higher oxid into a pervious receptacle, packing said receptacle in carbon, and heating to cause diffusion of carl o1i1nonoxid into the receptacle. a

3. The method which consists in placing tungstic acid in a pervious receptacle, packing the-receptacle in carbon, and heating to cause reduction of the tungstic acid by carbon monoxid diffusing into said recep tacle. I

4. The method of reducing-an oxid which consists in heating it with a reducing agent separated from it by a -pervious Wall to cause gas to difiuse back and forth through the wall to reduce the oxid and be in turn reduced by said reducing agent.

5. The method of producing chemical In Witness whereof, I have hereunto set Changes between two substances which conm hand this 5th day of January, 1909. sists in heating them in proximity to one an- WVILLIAM C. ARSEM.

other with an intervening pervious wall to W'itnesses: 5.0ausediff11sion of gas reacting with them. HELEN O'R'FoRn,

'- back and forth through said Wall. BENJAMIN B. HULL.

Copies of this patent ma y he obtained for fivg cents each; by addressing the Commissioner oi Patents,

V Waslfington, D. G. 

